The present invention relates to the technical area of working or processing components or workpieces by autogenous processes.
In the technical area of oxyfuel technology, time-honored processes that can be performed manually or automated mechanically for working or processing components or workpieces include various flame processes such as flame gouging, brazing, straightening, cutting, or flame heating.
In such cases, the flame used is a flame that is generated from a fuel gas or fuel gas mixture and an oxidant. The gases acetylene, ethene, methane, methylacetylene or propene, or gas mixtures thereof are used as the fuel gas. However other fuels may also be used instead of those listed, which are commercially available and important in the processing industry. Of all the fuel gases, acetylene has the highest flame temperature. Oxygen or even air is used as the oxidant.
Autogenous processes are processes in which materials are worked using a flame. For example, flame straightening is used to correct changes in shape that occur during the process of manufacturing components or workpieces. As may be learned from the “Handbuch der Flammrichttechnik” (Flame straightening technology manual), Welding Technology reference book series, volume 124, DVS-Verlag, Dusseldorf 1995, or the pamphlet “Tippy fur Praktiker. Flammrichten” (Tips for operators. Flame straightening) (June 2005 edition) published by Linde, in flame straightening, the component or workpiece is heated. In this way, undesired changes in shape are corrected.
Autogenous flame cutting is a type of thermal cutting process. The term flame heating refers to a process in which components are heated locally to enable forming. Flame brazing is a joining process in which a joint is created using solder. Flame gouging is a process for eliminating incorrect weld seams.
With regard to the equipment used in autogenous processes, different burners are used depending on the application in question or the thickness of the component or workpiece (see FIG. 1), such as single flame or single nozzle burners, or flame burners in which several individual flames issuing from the burner head form one common flame, or multiple nozzle burners, in which one flame each issues from several nozzles, or also special burners.
U.S. Pat. No. 2,286,591 discloses a method for working or processing at least one component or workpiece by autogenous processes and should also be mentioned in the review of the related art. Applications GB 539 470; U.S. Ser. No. 349,902; and U.S. Pat. No. 4,035,604 are also of some significance with respect to the technological background of the present invention.
In the manually or mechanically performed oxyfuel technology processes described above, in which open flames are used, particularly open fuel-oxygen flames or open fuel-air flames, it seems desirable to reduce the concentration of contaminants contained in the waste gas from the burner, particularly the concentration of nitrogen oxides (NOX), for example poisonous nitric oxide (NO) and/or nitrogen dioxide (NO2), and of other harmful compounds, not least in order to comply with toxic substance limit values, and thus also to minimize pollutant emissions and environmental damage, and thereby to limit to the extent possible any possible threat to the health of the burner operator.